Interpretive Summary: One of the most common ways poultry litter is used in Northwest Arkansas is as a fertilizer for pastures. Due to this practice phosphorus concentrations have built up in the soil, resulting in high concentrations of phosphorus in runoff . This study was started to examine the ability of five different grass species to reduce nutrient concentrations in runoff from agricultural fields. The five grasses used in this study were tall fescue, caucasian bluestem, bermudagrass, gamagrass, and switchgrass. Poultry litter was applied at a 4 ton/acre application rate. Runoff data that was collected from these grass plots showed that tall fescue had much lower runoff volumes and higher infiltration rates. There were no differences in the nutrient concentrations of the runoff between the different grasses. However, when these concentrations were multiplied by the different runoff volumes, the losses of phosphorus and nitrogen were much lower from the tall fescue plots. These results represent the grass species after approximately 14 months of growth. Data will continue to be collected as the grasses mature.

Technical Abstract:
The common practice of surface applying poultry litter to pasture land can leave the potential for excessive nutrient loss from these systems. Little research has been done to examine how the use of different forage species influence nutrient loss from pastures. The objective of this study was to evaluate the effect of five forage species at varying canopy heights (one week v six weeks growth post harvest ) on surface runoff volume and quality from pasture systems fertilized with poultry litter. The five forage species evaluated were: Alamo switchgrass (Panicum virgatum L.), Caucasian bluestem (Bothriochloa caucasia (Trin.) C.E. Hubb.), Greenfield bermudagrass (Cynodon dactylon (L.) Pers.), Pete Eastern gamagrass (Tripsacum dactyloides (L.) L.), and Kentucky-31 Tall fescue (Festuca arundinacea Schreb.). Poultry litter was applied annually at 8.97 Mg ha**-1. Simulated rain was applied at 50 mm h**-1 during spring, summer, and fall to examine seasonal variations. Soil samples (0-5 cm) were taken in conjunction with each rainfall simulation to determine soil nutrient levels. Runoff volumes, infiltration, and nutrient content of the runoff water will be reported.